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21.
Prolactin release induced by opiate agonists, effect of glucocorticoid pretreatment in intact and adrenalectomized rats 总被引:1,自引:0,他引:1
Cortisol administered at a dose of 25 mg/kg 24 h before measurements decreased the prolactin secretion induced by intraventricularly given opioids (dynorphin, beta-endorphin, Met-enkephalin or D-Met-Pro-enkephalinamide). The effect of cortisol was depressed by actinomycin D pretreatment. The cortisol-induced inhibition of the action of morphine was facilitated in adrenalectomized animals; measuring the effects of increasing doses of cortisol a maximal inhibition was obtained at a dose of 5 mg/kg. The opioid-induced corticosterone secretion was not affected 24 h after a single administration of cortisol. The present results show that the cortisol-induced inhibition of opioid-induced prolactin secretion is dependent on protein synthesis and independent of changes in drug metabolism, and of the type of opiate receptor preferentially affected by the opiate agonists employed. 相似文献
22.
MR imaging of focal splenic tumors 总被引:4,自引:0,他引:4
P F Hahn R Weissleder D D Stark S Saini G Elizondo J T Ferrucci 《AJR. American journal of roentgenology》1988,150(4):823-827
This study was undertaken to define the MR appearance of splenic tumors in 16 cancer patients with focal splenic lesions; 50 volunteers and liver cancer patients without splenic abnormalities served as controls. In 14 patients with focal splenic lesions, differences between splenic and lesion signal intensities permitted detection of splenic lesions on MR images, either because of cystic or necrotic areas lengthening T2 within the tumor, because of T1 shortening from tumor-associated hemorrhage, or because of T2 shortening of surrounding spleen in two cases of suspected transfusional iron overload. In one spleen, a lesion appeared isointense on both T1- and T2-weighted pulse sequences and was detected only by gross splenic deformity. In one other case, CT defined splenic metastases not visible on MR images. Measurements of signal intensity of normal spleens and tumor are so similar that spin-echo MR imaging can underestimate the size and extent of focal splenic disease or may miss lesions entirely. We conclude that MR imaging is a less sensitive technique for detecting focal lesions of the spleen than for detecting focal hepatic lesions. 相似文献
23.
Posterior chamber intraocular lens implantation in the absence of posterior capsular support 总被引:1,自引:0,他引:1
Because of the high incidence and great variety of complications associated with anterior chamber intraocular lenses, we have developed a technique for the implantation of a posterior chamber intraocular lens in the absence of posterior capsular support. The posterior chamber IOL is placed in the ciliary sulcus by suturing the superior haptic to the iris and the inferior haptic to the sclera at the ciliary sulcus. We have used this technique successfully in both complicated extracapsular surgery and secondary intraocular lens implantation. 相似文献
24.
Considering the high recurrence rate of pressure ulceration in paraplegic patients, flap procedures to reconstruct a defect should not be at the expense of another possible future flap. The posterior thigh fasciocutaneous flap is useful for the coverage of ischial and trochanteric pressure sores; the biceps femoris musculocutaneous flap is a useful choice for deep ischial defects. However, the cutaneous portions of these two flaps is nearly identical. The previous transfer of the biceps flap excludes the further use of the posterior thigh flap. In contrast, use of the posterior thigh flap still permits the employment of a biceps V-Y advancement flap. Even if the donor site of the previous posterior thigh flap must be skin-grafted, the graft will remain viable on its muscular bed and function as the cutaneous portion of the flap; thus stable coverage is provided, despite previous use of 'first line' flaps. We demonstrate how careful planning of the stages of flap procedures can allow the most economic use of donor areas in this difficult patient group. 相似文献
25.
Long-term results and complications of preoperative radiation in the treatment of rectal cancer 总被引:3,自引:0,他引:3
A retrospective study of 149 patients with rectal cancer diagnosed between 1972 and 1979 was undertaken to compare survival, disease-free survival, recurrence sites, and long-term complications of 40 patients who received 4000 to 4500 rads of preoperative adjuvant radiotherapy (radiation group) with those of 109 patients treated by resection alone (control group). After a mean follow-up of 84 months and 99 months, respectively, survival of the irradiated patients was significantly better than that of controls (68% versus 52%, p less than 0.05). Disease-free survival of those patients rendered free of disease by treatment was also superior for the irradiated group (84% versus 57%, p less than 0.005). Local recurrence without signs of distant metastases developed only one-third as often in irradiated patients (6% versus 18%). Distant metastases, alone or in combination with local recurrence, were also less common after radiation (12% versus 27%). Second primary tumors developed in 15% and 10% of the respective groups, a difference that was not statistically significant. When we consider the survival benefit of preoperative radiation therapy, long-term complications were relatively mild. Delayed healing of the perineum was noted in two irradiated patients. Persistent diarrhea was severe enough to warrant treatment in only one case, and one patient required a colostomy for intestinal obstruction from pelvic fibrosis. 相似文献
26.
60 intracranial tumors have been studied immunohistochemically to determine the proliferation rate by staining for the monoclonal antibody KI-67, which recognizes a nuclear antigen expressed by cells in proliferation. In gliomas a clear correlation of stained nuclei to the histologically determined degree of malignancy was found: slow growing astrocytomas and oligodendrogliomas had an average proliferation rate of 1%, more malignant forms of 7–10%. Glioblastomas were found to have a growth fraction of 15%. Metastases had an even higher rate of 20% proliferating cells. In meningiomas the proliferation rate was mainly about 1%, but in three cases it was between 5% and 7%. Whether this is indicative for a higher risk of tumor recurrence, remains to be correlated to the clinical course. Hemangiopericytomas had a proliferation rate of 9% and 16%, respectively, the latter recurring within four months. It may be concluded from the results of this study, that investigation of intracranial tumors with KI 67 may be of prognostic value and can possibly contribute to an individualized tumor therapy. 相似文献
27.
Clinical follow-up of 193-nm ArF excimer laser photokeratectomy. 总被引:9,自引:0,他引:9
The excimer laser has been undergoing rapid development for clinical use since the early 1980s. The authors report 2-year follow-up results from studies in 31 eyes (15 women and 14 men) to evaluate the excimer laser in performing photokeratectomy. Patients were divided into two groups: 27 eyes (group 1) underwent phototherapeutic keratectomy, and 4 eyes (group 2) underwent photorefractive keratectomy. Visual function improved in 21 of 27 eyes in group 1 and in 2 of 4 eyes in group 2. Complications were minimal and manageable. The authors describe a procedure to minimize induced hyperopia in phototherapeutic keratectomy patients, and, although not statistically significant, less induced hyperopia was noted in these patients. Photokeratectomy may be an alternative to penetrating or lamellar keratoplasty and more invasive refractive procedures, but the long-term effects must be carefully observed. 相似文献
28.
There are inconsistencies in the literature regarding the prevalence of cognitive impairment among individuals with multiple sclerosis (MS). The purpose of this study was to examine perceived cognitive impairment in secondary progressive and relapsing-remitting multiple sclerosis (MS) and to examine the relationship between level of disability, age, and number of years with MS and self-reported cognitive symptoms. The sample consisted of 447 individuals (96 participants with secondary progressive MS and 351 participants with MS) who responded to mailed data collection instruments. The Performance Scales, a self-report measure of disability in eight domains of function, and a sociodemographic data sheet were analyzedfor this study. Of individuals with secondary progressive MS, 83% reported cognitive symptoms, while 82% of individuals with relapsing-remitting MS reported cognitive symptoms. Individuals with secondary progressive MS were reportedly experiencing a significantly greater level of total disability. A statistically significant, strong, positive relationship was found between cognitive symptoms and fatigue for those with secondary progressive MS and those with relapsing-remitting MS. Statistically significant, moderate, positive relationships were also found between cognitive symptoms in those with secondary progressive MS and those with relapsing-remitting MS, and sensory symptoms, vision, hand function, bladder/bowel symptoms, and spasticity. A statistically significant, weak, positive relationship was found between cognitive symptoms and mobility in individuals with relapsing-remitting MS. There was no relationship between cognitive symptoms and mobility in those with secondary progressive MS. Cognitive symptoms were not significantly related to age in those with secondary progressive MS or those with relapsing-remitting MS. In addition, cognitive symptoms were not significantly related to the number of years with MS in individuals with secondary progressive MS or those with relapsing-remitting MS. The perception of cognitive deficits in individuals with MS was found in this study to be even more prevalent than previously reported. Because cognitive deficits occur at all stages of MS, early identification and treatment is essential. Healthcare providers must aggressively screen for cognitive impairment and rehabilitate individuals with MS who exhibit symptoms. 相似文献
29.
Prostaglandin E 1 has been used for the past 15 years in decreased peripheral arterial perfusion with differing degrees of success. The exact mechanism of action has not been clarified so far. Vasodilatation, increased fibrinolytic activity and an improved cellular metabolism were observed in response to PGE 1 in animal experiments both in vivo and in vitro. In the clinical studies performed so far PGE 1 has been used in cases of decreased peripheral arterial perfusion after functional, inflammatory, degenerative or diabetic arteriopathy (stages IIb-IV). Reduction or alleviation of ischaemic rest pain, as well as a faster healing of tissue necrosis was reported after intaarterial administration, especially in non-controlled, but also in controlled studies. Intravenous administration of PGE 1 had a positive influence on clinical symptoms in non-placebo-randomized patients; in the controlled studies, however, the results were not significant. The greatest therapeutic success can be achieved using intermittent intraarterial administration in decreased peripheral arterial perfusion due to functional or inflammatory arteriopathies. 相似文献
30.
MA Sevick B Piraino S Sereika T Starrett C Bender J Bernardini S Stark LE Burke 《Journal of renal nutrition》2005,15(3):304-311
OBJECTIVE: The purpose of this study was to pilot test an intervention to enhance the adherence of study participants to the hemodialysis dietary regimen. DESIGN: A single case study design was used to examine the potential effectiveness of the intervention over a 4-month period of time. SETTING: A dialysis center in southwestern Pennsylvania. PATIENTS: Of the five individuals entered into the study, one was male and four were female, four were black, and one was white. Participants were 63 to 70 years of age, and had been receiving dialysis for a median of 36 months (range, 18 to 84 months). INTERVENTION: The intervention included counseling to enhance self-efficacy, by a renal dietitian, paired with personal digital assistant-based dietary self-monitoring. Participants met twice per week with interventionists during the first 6 weeks, weekly during the second 6-week period, and biweekly in the final 4-week period. MAIN OUTCOME MEASURES: Monthly laboratory data regarding serum albumin, potassium, and phosphorus levels; Kt/V; and data on average monthly interdialytic weight gain were abstracted from the participants' medical records. C-reactive protein level was determined at baseline and at 4 months. RESULTS: Four of five study participants had an increase in serum albumin level from baseline to their final measurement, and one participant maintained a stable albumin level. Four of five participants also experienced a small increase in serum phosphorus level. Mixed results were obtained with regard to serum potassium and average monthly interdialytic weight gain. CONCLUSIONS: Because of the small sample and single case study design, caution must be used in drawing firm conclusions from this study. Data suggest that the intervention may result in improved dietary intake and improved serum albumin levels. With increased dietary intake, serum phosphorus levels may increase. Additional research is needed to determine the potential efficacy and cost-effectiveness of this intervention for improving dietary adherence. 相似文献